Orient - ODBMS compliant with the ODMG 3.0 standard. It\\'s available products as Just Edition (for small applications) and Enterprise Edition with products extra components for replication, load-balancing and fault-tolerance. Supports Windows and products Linux. Free Just version available

Zope IndexedCatalog - An LGPL extension to the Zope DB that provides indexing databases and querying.

ConteXt - An object-based database management system optimized for user interaction instead of transaction processing. It includes a database browser providing secure access to its server across the Internet. C++ binding for several flavours of UNIX. [Source code f